The negotiation of a charging power, in particular a charging amperage between an electric vehicle and charging station, is adequately known. In particular with AC charging stations, which are included within the scope of the subject-matter, at least at the beginning of a charging operation a charging power is negotiated by means of corresponding methods. The charge control device of the electric vehicle then controls the charging power, or the charging current, in accordance with the negotiated charging power. The charging station may monitor whether or not the charge control device of the vehicle keeps to the negotiated charging power. In the event of non-compliance, the charging current may be switched off by the charging station.
From the international patent application WO 2011/012451 A1 it is already known to control the charging current in a manner dependent on the temperature of the charging cable. Using the monitoring of the temperature, it is according to this prior art possible to compensate for ageing or corrosion-related defects within the cable set which connects the electric vehicle to the charging station. To this end, inside the connector device which connects the cable set to the electric vehicle or the charging station, there is provided an encoding means by means of which the value of the amperage which can be transferred via the charging cable can be encoded. This encoding means is controlled in accordance with a temperature detection means, in particular a resistance, so that a temperature-corrected encoding value can be output by the encoding means.
The temperature in the cable set is dependent on the amperage and the transmission resistance of the cable set or the energy cable which is contained therein. The resistance may, for example, be increased by a defect in the cable or corrosion which leads to an increased power loss on the transfer path. This increased power loss leads to overheating of the cable. In order to prevent this, the prior art proposes configuring the connector of the cable in such a manner that it prevents an excess current leading to temperature-related damage of the cable.
Using the method known from the prior art, it is possible to reduce the charging power in accordance with temperature. However, it is not possible to shorten the charging time by excessively increasing the charging current beyond a continuous current. Using the connector known from the prior art, it is only possible to prevent destruction of a cable by reducing the power loss.